Many electrical and electronic devices such as a light emitting package in a structure such as a mold frame, a chassis structure or a metal bottom cover. These can be used as a light source for a backlight unit of an LCD or as a light unit in an illumination field backlight unit. In general, there are edge-type backlight units and direct-type backlight units, depending on the position of a light source. Because of their excellent mechanical and electrical insulation properties, thermoplastic polymeric resin compositions are used to manufacture articles of various sizes and shapes, including without limitation chassis components, and housings. In many cases, because of the design flexibility and their low cost, polymer resin compositions have replaced metal in these applications. However, many of these applications require that the parts be in the vicinity of or in contact with heat sources such as electrical lights. It is therefore desirable to form these parts from materials that are sufficiently thermally conductive to dissipate the heat generated. While metal parts thermally conductive, they are also often electrically conductive, which can be undesirable in certain applications.
Thermoplastic resin compositions are generally thermally insulating and typically electrically insulating unless they contain large amounts of electrically conductive additives. Thus, a thermally conductive, electrically insulating thermoplastic resin composition would be desirable and could replace metals, and in particular, aluminum, in many applications.
U.S. Pat. No. 6,487,073 describes a case for dissipating heat from an electronic device, comprising a housing of a net-shaped moldable thermally conductive composite material of a polymer base matrix with thermally conductive filler, and in thermal communication with an electronic component with heat dissipating from a heat generating electronic component and therethrough. No mention is made of using particular thermal conductive fillers with thermoplastic polymer.